I believe the EGO solenoids are pretty low, but I have heard that some TIMMY noids were also pretty low draw... I personally Like higher drawing noids, just because I know the power is going somewhere. Remember, you can always regulate the power using capacitors inline.

SMC have low power consumption. Ego's use modified mac43's which are everything but efficient. Generally solenoids with pilot valves use less power. If you use solenoids under 1Watt you generally don't need a capacitor.